package package02章_变量与运算符;

public class index {

    public static void main(String[] args) {
        float ff1 = 123123123f;
        float ff2 = ff1 + 1;
        System.out.println(ff1);
        System.out.println(ff2);
        System.out.println(ff1 == ff2);
        String[] test = new String[1];
        System.out.println("------------------------Exercise1-----------------------");
        Exercise1.main();

        System.out.println("-----------------------VariableTest1------------------------");
        b_2_02_整型和浮点型变量VariableTest1.main(test);


        System.out.println("-----------------------FloatDoubleExer1------------------------");
        b_2_04_FloatDoubleExer1.main(test);

        System.out.println("-----------------------VariableTest2 测试字符类型和布尔类型的使用------------------------");
        b_2_03_字符类型和布尔类型VariableTest2.main(test);


        System.out.println("-----------------------StringTest 基本数据类型与String的运算------------------------");
        b_2_09_基本数据类型与String的运算StringTest.main(test);

        System.out.println("-----------------------StringExer1------------------------");
        b_2_10_StringExer1.main(test);
    }

}

/**
 * @author 尚硅谷-宋红康
 * @create 12:36
 */
class Exercise1 {
    public static void main() {
        double PI = 3.14; //圆周率

        double radius1 = 1.2;
        double radius2 = 2.5;
        int radius3 = 6;
        double mainji3 = PI * radius3 * radius3;


        System.out.println("第1个圆的面积：" + PI * radius1 * radius1);
        System.out.println("第2个圆的面积：" + PI * radius2 * radius2);
        System.out.println("第3个圆的面积：" + mainji3);
    }
}